(P) NATIONALGEOGRAPHICSOCIETY
shore, the little band of primitive humans
realized by dawn that they would have to
retreat.
Gathering their meager belongings, they
went to rouse a youth of perhaps 18 who had
lain ill for some time. One look told them that
the flood could threaten him no more; he had
died in the night. Quickly his companions
covered the body with brush to protect it
from the hyenas and other carnivores feeding
near by. Then they fled to high ground.
Inexorably the lake crept over the camp
site, engulfing the body, together with many
stone tools abandoned in the flight and the
bones of small animals the hunters had eaten.
Higher and higher the water rose, depositing
a layer of silt over all.
Again and again during what we call plu
vial periods - eras of increased rainfall prob
ably coinciding with ice ages farther toward
the poles - the lake rose and fell, adding layer
on layer of silt and sand on top of the camp
site. Finally the water vanished, leaving the
body entombed under several hundred feet
of sediments that had hardened to rock.
Earthquakes Opened Door to the Past
There our story might have ended but for
one of those quirks of nature that sometimes
seem to do man's work for him.
Some. 100,000 years ago - when the bones,
of our Stone Age man had lain buried for half
a million years - violent 'earthquakes con
vulsed the area, fracturing and reshaping.
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